If I reacted a 20g of baking soda and 20g of vinegar in a beaker, and the products after the reaction were only 38g, does this demonstrate the law of conservation of mass? Why, or why not? What could be done differently in the experiment?

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What is the percent by mass of oxygen in fe2o3

Nitrogen dioxide decomposes according to the reaction 2 no2(g) ⇌ 2 no(g) + o2(g) where kp = 4.48 × 10−13 at a certain temperature. if 0.70 atm of no2 is added to a container and allowed to come to equilibrium, what are the equilibrium partial pressures of no(g) and o2(g)